Ten years ago, our financial system began to crumble under the weight of reckless risk-taking on Wall Street and deregulation in Washington, plunging our nation into the Great Recession. Millions lost their jobs and homes, trillions of dollars in household wealth were swept away, and communities across the land were devastated.

Over the past 10 months, shrouded by the chaos, divisiveness and vitriol emanating daily from an unhinged White House, the triumvirate of Donald Trump, congressional Republicans and Wall Street have launched a broad assault on the financial market protections put in place in the wake of the financial crisis. Last week, Americans got a small glimpse of the offensive being mounted to deregulate the financial industry, as Trump moved to eviscerate the Consumer Financial Protection Bureau by installing an acting director committed to that agency’s demise. This was no isolated act, but rather part of a no-holds-barred attack on oversight of Wall Street that must be defeated to protect American families and our economy.

In 2009, the president and Congress created the Financial Crisis Inquiry Commission to investigate the causes of the financial crisis. In its final report, the commission concluded that the crisis was avoidable and was caused by widespread failures of regulation, recklessness on Wall Street, and a systemic breakdown in ethics and accountability. The facts of the commission’s report, which detailed pervasive fraud and corruption in the mortgage markets, have gone unchallenged in the years since its release.

But the facts never mattered to the big banks or to their political minions in Congress. Helped to their feet by a multitrillion-dollar-taxpayer bailout , and strengthened by a quick return to record profits and executive pay, the big banks from Day One have waged a fierce, rearguard action against financial reform. Wall Street was further emboldened to resist reform by the failure of the Department of Justice to prosecute any senior executives for wrongdoing — a failure that not only has undermined efforts to deter future malfeasance but also has rightly bred cynicism and anger about the fairness of our legal and political institutions.

Since 2008, financial firms have spent more than $1.5 billion in federal lobbying and contributed more than $1.6 billion to federal campaigns as they have sought to deprive regulators of the funds needed to do their jobs; block common-sense regulations; and, working hand in hand with their Republican congressional allies, harass and bully public officials charged with protecting our financial system.

With the levers of power now in their hands, Trump, congressional Republicans, and Wall Street have moved from defense to offense, with the clear agenda to return to the deregulatory policies and anemic oversight that led to the 2008 financial meltdown.

They have put people in charge of key agencies — Steve Mnuchin at the Treasury Department, Keith Noreika at the Office of the Comptroller of the Currency, Jay Clayton at the Securities and Exchange Commission, and Christopher Giancarlo at the Commodities Futures Trading Commission — whose common trait is their lifelong service in and loyalty to the financial industry. These conflict-ridden appointments will pave the way for weakened regulation, a particularly troublesome development in light of the Financial Crisis Inquiry Commission’s findings that the failure of regulators to rein in bank excesses, despite their legal authority to do so, was a seminal cause of the 2008 financial meltdown.

They are moving to gut the already feeble system of punishment for financial wrongdoing. Penalties levied by the SEC against publicly traded companies have dropped dramatically since Trump took office — from $702 million in the February to September 2016 time frame to $127 million in the same period this year. In addition, the SEC’s co-director of enforcement recently indicated that the agency may back away from its recent drive to obtain admissions of wrongdoing as part of settlements — something that has happened in only 2 percent of enforcement cases filed from 2014 through 2017. The message to the financial industry is clear: Even if existing financial rules stay in place, there is no need to worry — the cops will be pulled off the beat.

And, they are methodically taking down individual pillars of protection — loosening oversight of AIG, the recipient of a $182 billion taxpayer bailout; repealing the Consumer Financial Protection Bureau rule that gave consumers the right to go to court when wronged by financial institutions; and blocking the fiduciary rule, which requires that financial advisers act in their client’s interests — as the Treasury Department readies more sweeping deregulatory changes.

Time and again, history has proven that unfettered deregulation and deference to Wall Street comes to no good end. The time to act to protect consumers and to prevent the next financial crisis is now, not after the bulwarks of protection have been torn down.

Every member of Congress and every candidate for federal office needs to hear loudly, clearly, and immediately that we expect them to be on the side of American families and business, not on the side of financial predators. If we do not rise up, then, as we know from experience, we will pay a dear price.

Phil Angelides, former state treasurer of California, was chairman of the Financial Crisis Inquiry Commission, which conducted the nation’s official inquiry into the financial crisis of 2008. To comment, submit your letter to the editor at SFChronicle.com/letters.